a) Indicating Instruments: These instruments make use of a dial and pointer for showing or indicating magnitude of unknown quantity. The examples are ammeters, voltmeter etc.

b) Recording Instruments: These instruments give a continuous record of the given electrical quantity which is being measured over a specific period.

The examples are various types of recorders. In such recording instruments, the reading are recorded by drawing the graph. The pointer of such instruments is provided with a marker i.e. pen or pencil, which moves on graph paper as per the reading. The X-Y plotters is the best example of such an instrument.

c) Integrating Instruments: These instruments measure the total quantity of electricity delivered over period of time. For example a household energymeter registers number of revolutions made by the disc to give the total energy delivered, with the help of counting mechanism consisting of dials and pointers.